The present invention relates to an improved roll product and an improved method and apparatus utilized in the manufacture of such roll product. A number of arrangements are disclosed in the prior art whereby the tail portion or outer terminal convolution of a roll product such product such as paper toweling, toilet tissue, and the like, is secured to the underlying convolution thereof. In particular, attention is directed to U.S. Pat. No. 3,393,105 which issued July 16, 1968 to Clair W. Tellier, Jr. and to copending U.S. application Ser. No. 194,159, filed Nov. 1, 1971 in the name of Ellsworth A. Hartbauer et al.
As explained in the aforementioned U.S. Pat. No. 3,393,105, in paper converting operations it is common practice to rewind from a large parent or supply roll a plurality of elongated cants which are then severed into individual rolls. One of the many problem areas arising during converting is that of securing the tail portion or outer terminal convolution of the cant to the underlying or contiguously subjacent convolution prior to the cant being advanced into the severing and wrapping machinery in which the relatively long cant (or log, as it is sometimes called) is segmented into a plurality of small rolls which are then wrapped for shipment and sale. If the tail of the cant is not secured to the underlying convolution, the severing and wrapping unsightly may not be properly performed, in which event the wrapping machinery may jam or, if the wrap is successfully performed, excess paper from the completed roll product may extend from the wrapper, thereby resulting in an package.
The aforementioned U.S. Pat. No. 3,393,105 and the aforementioned copending application U.S. Ser. No. 194,159 both disclose arrangements for adhesively securing the tail portion of a cant to the immediately underlying convolution, thereby obviating the prior requirement for the presence of personnel whose function it is to manually secure the free tail of the cant prior to delivery thereof into the servering and wrapping machinery. In U.S. Pat. No. 3,393,105 the adhesive securing operation is carried out by rotating the roll product cant in a direction tending to wind the tail portion thereabout, unwinding the tail portion therefrom, depositing a predetermined quantity of adhesive directly onto the tail portion while the tail porting is unwound therefrom at a pre-established location adapted to underlie the rewound tail portion, and rewinding the tail portion about the roll product so that the tail portion overlies the adhesive which thereby secures the tail portion to the convolution underlying same.
The arrangement disclosed in copending application Ser. No. 194,159 differs from that disclosed in the Tellier patent in a number of significant respects, although the end objective of adhesively securing the tail portion of a roll product to the underlying convolution thereof is the same. In the application, while the tail portion is unwound from the rest of the roll, adhesive is applied to the roll product convolution normally underlying same in the form of discrete dots of adhesive which are ejected through a plurality of nozzles spaced along the length of the roll product cant. This arrangement provides a number of advantages over that disclosed in the Tellier patent. Since the advantages are clearly set forth in the specification of the aforementioned application, they will not be gone into here.
Although the apparatus and methods disclosed in the aforementioned patent and application are in general quite satisfactory, there are certain characteristics of the completed roll product produced thereby that could be advantageously improved upon. In particular, the single ply or multi-ply roll products produced by the apparatus and methods of the aforementioned patent and application have a common characteristic; that is, the tail portion thereof lies in abutting engagement with the underlying convolution as a single layer of the single or multi-ply material of which it is comprised. While the roll products produced according to the teachings of the aforementioned patent and application offer significant advantages over prior art roll products insofar as easy-opening characteristics are concerned, some difficulties are still encountered on occasion by the purchaser insofar as starting or opening of the final roll product featuring the adhesively secured tail portions is concerned. In other words, the roll products produced according to the teachings of the aforementioned patent and application share some of the defects, although to a lesser extent, of conventional prior art roll products insofar as opening characteristics are concerned. Such undesirable opening characteristics include lack of a readily graspable element to the start the roll, inadequate material strength at the location of manual grasping such that elongated tears or rips in the roll product material are inadvertently made by the customer, inadvertent separation of plies upon opening of the roll in the case of multi-ply roll product materials, and an overall package appearance that features a somewhat ragged tail portion free end.